JasymcaJasymca - Jasymca is a symbolic calculator. It solves and manipulates equations, handles basic calculus problems, and provides a few more typical functions of computer algebra systems. The syntax is loosely related to GNU-Maxima. While it is fun to play with mobile devices, it teaches the use of computer algebra systems, and may even be used to solve some real world problems

MIDP Graphing CalculatorMIDP Graphing Calculator - A graphing calculator for Java MIDP cell phones.
It actually implements a small programming language, parsing expressions into trees. One can define functions with an arbitrary number of parameters, and use the functions in java.lang.Math in addition to the normal operators

Powerful-XcalculatorAbout
I have written this calculator with 2d and 3d plot function as student project

FrinkFrink - Frink is a programming language and calculating tool designed to help you make real-world calculations.
Frink is different than other calculating tools in that it tracks units of measure through all calculations. Thus, you can add feet and meters, multiply by grams, divide by pounds, and Frink does the right thing through all calculations

Calculator 4 MEverybody needs a calculator. "Calculator 4 M" easy to use and beautifully designed to do things better than your phone or handheld calculator ever did

Graphing CalculatorGraphing Calculator - FREE app, designed to turn your cell phone into a Graphing Calculator.
It should work on all phones that support J2ME, like Nokia, Blackberry, Motorola, LG, Samsung, Sony Ericsson and more (specifically MIDP 2.0 and CLDC 1.1)

HorsePowerHorsePower is J2ME scientific calculator optimised for use on mobile phones, with the appearance of the classic range of Hewlett Packard calculators (MIDP 1.0 and CLDC 1.0)

EasyCalcFreeEasyCalcFree - A very simple calculator. Enter a list of up to 10 numbers, add labels.
Comes with hyper-intelligence: You can write *, x, /, div, divide, subtract, plus, minus, times, takeaway, or pls, tms, add...you will still get the same result